The search for "what works" is crucial for making well-informed, non-arbitrary, defensible decisions about selecting and implementing behavioral health-related interventions. One significant modality for assisted decision-making has been the creation of repositories of evidence-based programs and practices ("EBPRs"). A preliminary Internet search yielded more than 40 repositories in the form of websites with databases or compilations of recommended programs. Additionally there exist many published meta-analyses and systematic reviews. These sources all identify or promote interventions in terms such as "evidence-based," "effective," "best practices," or "promising practices." Familiar examples are the National Registry of Evidence- Based Programs and Practices (NREPP), the CDC's Diffusion of Effective Behavioral Interventions website and the Cochrane Reviews. Unfortunately, the proliferation of such potentially useful repositories has been accompanied by often dramatically different purposes, criteria for inclusion, definitions of acceptable "evidence," and standards for designating interventions as "effective" or effective to a certain degree. Thus, policy-makers and practitioners can be presented with ambiguous, inconsistent and incomplete recommendations for putative evidence-based interventions. In this situation, it may not be meaningful to mandate the use "evidence-based" programs, as is becoming a trend. These proliferating EBPRs have not yet been comprehensively and critically examined to better understand the relations among them and how best to utilize them for decision-making and resource allocation. The study will: 1. Compile a comprehensive list of EBPRs for behavioral health-related interventions. 2. Classify those EBPRs according to their purposes, methodologies, acceptable types and standards of evidence, and other factors that are used to include and certify "effective" interventions. 3. Determine the practical consequences of using different types and standards of evidence for including and certifying interventions as effective (e.g., to what extent and for what reasons are the same interventions rated differently by different EBPRs?). The results of this critical study of EBPRs would increase understanding of the strengths and limitations of these repositories, indicate how best to use them in decision-making, and thus aid in disseminating effective behavioral health-related programs in society. PUBLIC HEALTH RELEVANCE: The results of this critical study of evidence-based program registers would increase understanding of the strengths and limitations of these repositories, indicate how best to use them in decision-making, and thus aid in disseminating effective behavioral health- related programs in society.